Robotic arms have become commonplace in industrial factories for a variety of jobs. One such job is for welding metal parts together. The robotic arm that is used for welding commonly has a set of jaws for initially clamping the parts together and a weld tip which is then moved into position and welds the parts together. Pneumatic piston and cylinder assemblies have been expeditious and economical mechanisms to independently control the position of the jaws and weld tip.
The piston and cylinder assembly for the weld tip and the piston and cylinder assembly for the jaws are packaged in a common frame that is mounted on the robotic arm itself. Actuator controls for both piston and cylinder assemblies are also mounted on the robotic arm. Pneumatic piping leads from the actuator controls to the piston and cylinder assemblies. All of these components including the separate housings for the actuators, and the pneumatic piping add a significant amount of weight onto the robotic arm. The extra weight on the robotic arm provides several disadvantages. Firstly, the robotic arm must be built stronger to support the weight. Secondly, the extra weight also tends to make the arm less agile and maneuverable. Stronger and more expensive motors need to be employed to move the larger and heavier arm.
What is needed is a lightweight pneumatic piston and cylinder assembly for a robotic arm that has built-in actuators.